StateDemoTest.php

<?php

namespace Drupal\Tests\form_api_example\FunctionalJavascript;

use Drupal\FunctionalJavascriptTests\WebDriverTestBase;
use Drupal\Core\Url;

/**
 * @group form_api_example
 *
 * @ingroup form_api_example
 */
class StateDemoTest extends WebDriverTestBase {
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * Our module dependencies.
     *
     * @var string[]
     */
    protected static $modules = [
        'form_api_example',
    ];
    
    /**
     * Functional tests for the StateDemo example form.
     */
    public function testStateForm() {
        // Visit form route.
        $route = Url::fromRoute('form_api_example.state_demo');
        $this->drupalGet($route);
        // Get Mink stuff.
        $page = $this->getSession()
            ->getPage();
        // Verify we can find the diet restrictions textfield, and that by default
        // it is not visible.
        $this->assertNotEmpty($checkbox = $page->find('css', 'input[name="diet"]'));
        $this->assertFalse($checkbox->isVisible(), 'Diet restrictions field is not visible.');
        // Check the needs special accommodation checkbox.
        $page->checkField('needs_accommodation');
        // Verify the textfield is visible now.
        $this->assertTrue($checkbox->isVisible(), 'Diet restrictions field is visible.');
    }

}